Nanostructured metal-oxide thin film towards the electronic device applications

Today, most of the low voltage electronics and opto-electronic devices are based on silicon technology. Metal oxide nanostructured semiconducting materials could be one of the alternatives for such devices. Metal oxide semiconductors are economical and can be easily synthesised by wet chemical processes. The formation of pn-junction is an important task for converting any two semiconducting materials interface to suitable application like rectifiers, photodetectors, light emitting diodes (LED), photovoltaic devices and lasers etc. The low cost semiconductor metal oxide materials like NiO, CuO, ZnO, TiO2, SnO2 are useful to develop pn-junction for such application. These metal oxides are easily synthesised by wet chemical process like chemical bath deposition (CBD), hydrothermal deposition (HTD), and spin coating techniques. In this present work, the ITO/NiO and NiO/ZnO two different junctions have been prepared using wet chemical processes. The morphological studies are performed by using scanning electron microscopy (SEM) and I-V characterisation studied using Keithley source meter. I-V characterisation confirmed the formation of pn-junction with rectification ratio of 22.4 and 15.7 at 2 V for NiO/ITO and NiO/ZnO junction respectively. The high ideality factor 2.06 and 2.2 depicts the high recombination of hole-electron carrier at diffusion region.